MEXICO CITY — The recent changes ordered by new President Enrique Peña Nieto to Mexico’s anti-narcotics partnership with the United States have produced markedly different reactions here and in Washington, underscoring what appear to be diverging perceptions of the drug war’s goals and the costs of fighting it.

Peña Nieto’s decision to limit the ability of American agents to operate in Mexico has been met with dismay by U.S. law enforcement agencies, which left a heavy footprint under the previous administration of Felipe Calderon. They warn that intelligence sharing will suffer if they can no longer choose which Mexican force — the army, navy or federal police — to give sensitive information to; they’ve been instructed to now funnel everything through Mexico’s Interior Ministry instead.

The agents also caution that the personal relationships developed under Calderon will fray if they are no longer welcome to work side by side with trusted partners at sites such as the joint command centers where Americans helped spy on Mexican narcotics traffickers and direct operations against them.

Yet here on the southern side of the fight, where gangland violence has taken 60,000 to 90,000 lives in the past six years, there is little surprise that Peña Nieto would move to reformat the relationship. It is a change that has been coming for a long time.

Standing opposite President Obama at a news conference here May 2 during the U.S. president’s recent visit, Peña Nieto insisted that drug war cooperation would remain robust but that Mexico wants a more “efficient” strategy.

“Let me say it very clearly,” he said. “Under this new strategy, we’re going to order things up. We’re going to make it institutional. The channels will be very clear. We’re going to use one single channel in order to be more efficient, to attain better results.”

It is the meaning of “better results” that the two countries increasingly differ on.

Seeking change

Seizing dope and smashing cartels were the shared goals for Mexico and the United States under Calderon. He allowed U.S. agencies unprecedented latitude to gather intelligence on drug cartel suspects and decide which Mexican security forces were trustworthy and effective enough to share it with. To safeguard against the gangsters’ corrupting powers, the Americans developed “vetted” units of elite drug-war fighters, relying heavily on Mexico’s marines to be a lethal strike force against high-level targets.

But the flow of drugs north and the death toll in Mexico remained virtually undiminished as fallen mafia capos were quickly replaced by new leaders and the troubles of the border region spread south.

Frustrated Mexicans were looking for a change, and on the campaign stump last year and since taking office in December, Peña Nieto pledged that “reducing violence” would become his overarching security goal. In private, his aides characterized the Calderon years as a free-for-all that put tens of thousands of troops on the streets but didn’t make Mexico safer.

Peña Nieto’s changes to U.S. security cooperation generated little news media attention here, and the president’s political rivals have been quiet, as well. Nor has there been controversy over Peña Nieto’s plans to recast the Merida Initiative, the $1.9 billion U.S. security aid package signed by Calderon. It will shift from supplying Mexico with military hardware and training to strengthening the country’s dysfunctional criminal justice system and preventing violence via social programs.

Peña Nieto eventually plans to send Mexican troops back to the barracks and gradually replace them with a paramilitary-style national police force modeled after France’s National Gendarmerie. But it may take years for the new force to be ready.

His move to rein in American agents has been mostly depicted by analysts in terms of Mexican nationalism, consistent with the legacy of Peña Nieto’s Institutional Revolutionary Party (PRI), which ruled Mexico for most of the 20th century.

“The PRI has always had misgivings about Uncle Sam, and every new PRI president has tried to diminish dependence on the U.S.,” said George Grayson, a Mexico scholar who has written extensively about the drug war. “It is traditional PRI nationalism and shouldn’t surprise anyone,” he said.

But Peña Nieto officials argue that the centralization of intelligence sharing is a common-sense move intended to streamline coordination among its security forces. And although U.S. officials worked more closely than ever with Mexican counterparts under Calderon, the relationship took several bruises.

Among the more trust-damaging was the botched gun-walking scheme dubbed Fast and Furious and other U.S. operations like it, which let hundreds of illegal firearms fall into the hands of Mexican gangsters. American agents also ended up sowing division among Mexico’s security forces by seeming to favor the marines over its army and federal police.

A possible chill

The new protocols mean that the U.S. Drug Enforcement Administration, CIA and other agencies can no longer bypass Mexico’s central government to work directly with their trusted military contacts to pass along tips on the whereabouts of cartel targets.

American officials say that will put a deep chill on cooperation, and they have raised doubts about Peña Nieto’s will to carry forward with the fight.

But a former high-ranking U.S. military officer who worked with Mexico for years said the move is consistent with Peña Nieto’s longer-term strategy of demilitarizing Mexican law enforcement and rerouting civilian intelligence away from the armed forces, which have been strained by a crime-fighting role they were never trained for.

The former commander also said that military-to-military ties between the United States and Mexico are likely to remain as strong as ever and that intelligence generated by the U.S. military on the whereabouts of drug shipments and narcotics traffickers can still be shared with Mexican armed forces under existing agreements.

What will be different, he said, is that U.S. civilian agencies such as the DEA or CIA won’t be allowed to work directly with Mexico’s military. He spoke on the condition of anonymity because he still works in the region.

In public remarks made during his recent visit to Mexico, Obama struck a deferential tone. “It is obviously up to the Mexican people to determine their security structures and how it engages with other nations, including the United States,” he said.

Alejandro Hope, an analyst and ex-Mexican intelligence official, predicted that Peña Nieto and his allies might fall back on the Calderon strategy if their approach does not produce swift dividends. “Once they don’t get the reduction they promised, they’re going to need more help from the U.S.,” Hope said. “And a year from now, it’s going to cost them even more.”

Nick Miroff is a Latin America correspondent for The Post, roaming from the U.S.-Mexico borderlands to South America’s southern cone. He has been a staff writer since 2006.

Comments our editors find particularly useful or relevant are displayed in Top Comments, as are comments by users with these badges: . Replies to those posts appear here, as well as posts by staff writers.

To pause and restart automatic updates, click "Live" or "Paused". If paused, you'll be notified of the number of additional comments that have come in.

Comments our editors find particularly useful or relevant are displayed in Top Comments, as are comments by users with these badges: . Replies to those posts appear here, as well as posts by staff writers.